The Briton began the tournament short of matches after illness and injury.

"I was close to reaching another Slam final when I was not playing well and feeling really, really bad before the event," Murray told BBC Sport.

"I'm not happy - I'm disappointed, frustrated and tired after a long couple of weeks - but I'm proud I put myself into that position, when there were a lot of doubts coming into the event and I didn't feel great at the beginning of the tournament.

"I worked through it, accepted the position I was in, and gave a reasonable account of myself considering those things."

Murray's next match will be at the Aegon Championships on 20 June

Wawrinka hit 87 winners in a gripping contest that pitted the 2015 champion's attacking prowess against the defensive skills of Murray.

The Swiss, 32, ultimately proved too strong as he made amends for losing to Murray at the same stage last year in Paris.

"He played too well in the end," said the 30-year-old world number one.

"Physically I didn't feel my best at the end. It is more like I didn't have enough weight on my shot at the end of the match to put him under any real pressure."

Murray struggled with shingles, two heavy colds and an elbow injury in the first half of 2017, and arrived at Roland Garros with just 16 wins to his name.

Over the course of six matches in Paris, he spent 18 hours and 17 minutes on court.

Victories over Juan Martin del Potro and Kei Nishikori gave particular encouragement as he looks ahead to the grass-court season.

"I do feel like having an event like this can give me a boost," said Murray, who will play his first match on grass at the Aegon Championships on 20 June.

"On the grass I'll hopefully move well, that's an important part of my game and something I struggled with at a few points during this clay season.

"And the serve. That's something I struggled with the last couple of months.